The present invention relates to a device for applying adhesive in a slitter-winder of a fiber web machine.
In manufacturing lines known from the prior art fiber web making takes place as a continuous process. A fiber web completing in a machine is wound with a reel-up around a reeling shaft i.e., a reel spool, into a machine roll (a parent roll). The purpose of reeling is to modify the web manufactured as planar into a more easily processable form. In the reel-up the continuous process of the machine breaks for the first time and shifts into periodic operation. This periodicity is tried to be made with efficiency as good as possible in order not to waste already done work in earlier process stages.
The machine roll web produced in fiber web making is full-width so it must be slit into partial webs with suitable width and the partial webs are wound to partial web
rolls (customer rolls) with suitable length and diameter for the customers. The slitting and winding take place as known from prior art in an appropriate separate machine, i.e. in a slitter-winder.
As known from the prior art, in the slitter-winder the machine roll is unwound, the wide web is slit on the slitting section into several narrower partial webs, into at
least two partial webs, which are wound up on the winding section around winding cores, such as spools, into customer rolls. When the customer rolls reach a desired length and diameter the partial webs are cut in the cross-direction. Tails of the partial webs are attached to the surfaces of customer rolls by applying adhesive to the surface of the fiber web, which adhesive then attaches the tails to the surface of the customer rolls. When the customer rolls are completed, the slitter-wider is stopped and the rolls, i.e. the so-called set, is removed from the slitter-winder after which the process is continued with the winding of a new set. These stages are repeated periodically until paper runs out of the machine roll, whereby the machine roll change is performed and the operation starts again.
It is known from prior art to apply adhesive for attaching the tail of the fiber web to the surface of the customer roll by means of a device traversing in the transverse direction of the running direction of the web. In publication GB 2061234 an adhesive applying apparatus is described in which adhesive is introduced while the web is moving and an adhesive stripe substantially in the transverse direction of the running direction of the web is applied.
WO publication 2008/148937 describes an apparatus for applying adhesive onto a moving web, containing an application head provided in connection with a support structure extending essentially in the transverse direction across the web, the support structure comprising a guide extending across the web into which the application head has been disposed movably, and the application head has been arranged to form onto the surface of the web an adhesive stripe essentially in the transverse direction in relation to the web running direction while the web is moving. This prior art apparatus comprises means for changing the movement direction of the application head during the application of adhesive and/or that the application apparatus includes means for changing the movement speed of the application head during the application of adhesive. According to one embodiment of this prior art apparatus it comprises more than one application head and in FIG. 4 of the WO publication is disclosed one example for this embodiment. In this example the apparatus comprises two application heads that according to the figure each have a carriage of its own and own movement path on the support structure that extends across all the partial webs and as shown in the figure over the web area in each end.
Even though the above apparatus has in most cases proven to be well functioning it is not suitable in all cases and it is problematic in particular in connection with narrow machines. In connection with narrow machines the space requirement in the width direction is more than is available and thus in prior art two separate, staggered support structures have been used.
The device for applying adhesive in a slitter-winder has typically been located underneath the web and under the slitter-winder between carrier beams. In an operation situation when adhesive is applied, high movement speed of the adhesive nozzle is needed which leads to a need of high acceleration speed.